Apparatus for screening and loading coal



March 14, 1939. I G. s. JAXON 2,150,717

APPARATUS FOR SCREENING AND LOADING COAL Filed Oct. 18, 1955 8 Sheets-Sheet l March 14, 1939. s. s. JAXON APPARATUS FOR SCREENING AND LOADTNG GOAL Filed Oct. 18, 1955 8 Sheets-Sheet 2 grvucnhw 1700765: Jazm March 14; 1939.

G. s. .JAXON 0,

FOR SCREENING AND IJOADTNG COAL Filed Oct. 18, 1935 APPARATUS 8 Sheets-Sheet 3 March 14, 1939. 5 JAXON APPARATUS FOR SCREENING AND LOADING COAL Filed Oct. 18, 1955 8 Sheets-Shet 4 3 W m 'wzyedf e/axm March 14, 1939. G. s. JAXON APPARATUS FOR SCREENING AND LOADING GOAL 0 Filed Oct. 18, 1935 8 Sheets-Sheets March 14,. 1 939. G 5 JAXQN 2,150,717

APPARATUS FOR SCREENING AND L' OADING COAL Filed Oct. 18, 1935 a Sheets-Sheet e as a2 30 Jawchfm demyeJZ/mm March 14, 1939. G s JAXON 2,150,71T

APPARATUS FOR SCREENING AND LOADING COAL Filed 001;. 18, 1935 8 Sheets-Sheet 7 March 14, 1939.

G, s JAXON APPARATUS FOR SCREENING AND LOADING COAL Filed Oct. 18, 1935 8 Sheets-Sheet 8 Patented Mar. 14, 1939 UNITED STATES APPARATUS FOR SCREENING AND LOADING COAL George S. .Faxon, Chicago, 111., assignor to Link- Belt Company, a corporation of Illinois Application October 18, 1935, Serial No. 45,647

19 Claims.

This invention relates to new and useful improvements in apparatus adapted for screening and loading coal into trucks, railway cars and the like, and is particularly adapted for han- 3 dling lumps, or the larger sizes of coal,to be delivered for domestic consumption.

Coal dealers serving cities or other large communities in the vicinity of mines usually receive their supply of coal direct from the mines, pass the coal through suitable weighing, screening, and sizing apparatus and then store the different grades or sizes of coal in separate, relatively large bins forming what are termed local trade pockets. The coal is loaded from these bins into trucks or wagons for delivery to the consumers.

Considerable difiiculties are encountered in storing sized lumps, or the larger sizes of coal, in bins, withdrawing the coal from the bins at a fixed rate, removing the degradation fines made in the operations of storing and removing the coal from the bins, disposing of the degradation, and loading the properly conditioned or sized coal into trucks or wagons of various sizes and heights and which may be either covered or uncovered. It is believed that a recital of these difficulties will enable one to better understand and more fully appreciate the efficient manner in whichthe apparatus disclosed herein operates to overcome the same. These difficulties are as follows:

(1) In order to store a large quantity of coarse coal, it is usually necessary to provide a bin having considerable depth and length. Therefore, as the coal is lowered into the bin, considerable degradation is made and more degradation is made as the coal is withdrawn from the bin.

(2) Where large lumps of coal are to be handled, it is necessary to have a large opening or gate through which the coal flows to the screening and loading apparatus, and due to the depth or head of the coal above the opening, the large gate tends to permit the coal to flow out in a thick mass at a rate which cannot be properly loaded onto the trucks or cars. The depth of the coal passing over the loading and screening apparatus also prevents the removal of the degradation as it cannot come in contact with screening apparatus provided for that purpose. The loading apparatus also has to be extremely large, cumbersome and hard to handle.

(3) It is essential that the degradation fines be removed from the coal during its'travel from the bin to the transportation conveyance. Complete removal of the degradation cannot be accomplished without agitating or turning over the ltunps to permit the fines to pass therebetween to the screening apparatus for removal. It has been found to be desirable to feed the 5 coal from the bin by withdrawing it at a comparatively slow rate so that the loading apparatus can readily handle the same. The removal of the degradation cannot be accomplished in one stage for the above referred to feeding, agi- 10 tating and tumbling or turning operations produce some further degradation after discharge from the feeder which must be removed before the coal is finally delivered to the conveyance.

(4) Some of the trucks are covered, therefore the loading apparatus cannot be hoisted upwardly except to a certain extent. Consequently, it must be adapted for long or short and open or covered trucks.

(5) After the degradation has been removed, it is desirable to have means for collecting and delivering it to a bin or some other point from which it is later recovered and disposed of.

(6) If an ordinary gate or chute is provided to control the rate of discharge from the bin, it is impossible to adjust the gate opening so as to permit the larger lumps to pass without bridging or clogging at the opening and the coal will not flow through the gate in a sufficiently thin stream to permit the removal of degradation fines,

The primary objects of this invention are to provide feeding means for controllably damming the coal at the bin discharge opening to prevent avalanching or flushing of the coal from the bin, withdrawing the dammed coal through said opening at a slow practical rate and in a sufiiciently shallow stream to permit proper handling of the coal while removing degradation and loading into conveyances for delivery, agitating and tilting the lumps to permit the degradation to fall therebetween, and screening out the degradation resulting from storage of the coal in large, high bins; to provide rescreening means which will remove the degradation fines formed by or possibly not completely removed by the screening action of the feeding means; to provide means for disposing of the degradation removed by the feeding means and the screening means; to provide loading mechanism which will permit the properly conditioned coal to be deposited in either covered or uncovered trucks, wagons or the like carefully without undue or excessive breakage, and to provide means for pro- .condition to be delivered to consumers tecting all of the mechanism of the aforementioned apparatus from the weather.

Other objects and advantages of the invention will be apparent during the course of the following description.

In the accompanying drawings forming a part of this specification and in which like numerals are employed to designate like parts throughout the same:

Figure 1 is a side elevational view of a local trade coal pocket employing the features of the coal loading and screening apparatus embodying this invention,

Figure 2 is an end elevational view of the trade pocket illustrated in Fig. 1, with one of the loading and screening devices illustrated in operative relation with respect to an uncovered truck.

Figure 3 is a detail side elevational view of a loading and screening device'operatively associated with a covered truck,

Figure 4 is a detail side elevational view of a coal screening and loading apparatus embodying this invention,

Figures 5a and 5b collectively illustrate in longitudinal vertical section the coal screening and loading apparatus disclosed in Fig. 4,

Figure 6 is a fragmentary, longitudinal, horizontal sectional view of the loading and screening apparatus taken on line 6-6 of Fig. 4,

Figure '7 is a detail side elevational view of a form of grizzly disk embodying this invention,

Figure 8 is an elevational view taken at right angles to Fig. 7.

Figure 9 is a side elevational view, partly in section, of a modified form of coal feeding, agitating, and screening apparatus which forms a part of the loading and screening apparatus embodying this invention,

Figure 10 is a horizontal sectional view taken on line l0lll' of Fig. 9, and

Figure 11 is a similar view to Fig. 9 but show-- ing a further modified form of coal feeding, agitating, and screening mechanism.

The drawings, wherein like reference characters are employed to designate like parts throughout the same, first will be referred to for the purpose of describing the broad inventive concept embodied in the apparatus disclosed therein.

Referring particularly to Figures 1 and 2, the reference character A desigates in its entirety a local trade coal pocket which includes a desired number of large, high bins a which are employed for receiving the different sizes of coal to be stored in the pocket. The coal, when received directly from the mine, is passed through suitable weighing, sizing, and screening apparatus, (not shown) and is delivered to the pocket and properly distributed in the'appropriate bins a by means of the conveyor mechanism B and associated instrumentalities, as illustrated in Fig. 2.

The coal when delivered to the trade pocket A by the conveyor mechanism B may be in proper However,'the depositing of the coal in the bins a and the storing of the coal in these bins produce degradation fines which must be removed to permit the delivery of clean coal to conveyances em ployed for carrying the coal to the consumers.

To permit proper removal of the degradation fines made in the bins, the coal must be fed through the discharge openings or gates to the screening mechanism at a reasonable rate and in a relatively shallow stream to permit the screening apparatus to properly remove the fines.

When lump coal is being handled, it also is necessary to agitate or tilt the lumps to release therefrom the fines so that the latter may be properly removed by the screening apparatus.

For the purpose of accomplishing this proper feeding and screening of the coal withdrawn from the bins, rotary grizzly screening apparatus, designated in its entirety by the reference character C is illustrated in Fig. 2 as being provided for each one of the loading booms desighated by the reference character D.

The loading booms D are each formed of a fixed boom section d and a vertically swinging end section 07 A cable form of hoist E is provided for vertically swinging the outer section (1 of each boom. These swinging boom sections (1 may be manipulated in any suitable manner to facilitate the loading of coal into trucks and wagons of different sizes and characters.

In Figure 2 there is illustrated a conveyor F for each loading boom D. The conveyor functions to move the screened coal from the feeding mechanism C to the extremity of the outer boom section 11 to permit the coal to be loaded in a conveyance G properly associated with the boom. The provision of the conveyor F will permit the coal to be moved to the conveyance regardless of the inclination of the outer boom section 01'. In other words, it is not necessary to have the sections of the boom arranged at a sharp inclination sufiicient to effect gravitational feed of the coal to the conveyance when the conveyor F is employed. This results in the careful depositing of the coal in the conveyance without undue or excessive breakage.

In Figure 3 there is disclosed a modified form of outer boom. section d which is adjustably supported by a cable hoist mechanism E. This cable hoist mechanism is connected to the boom section d at a sufficient distance inwardly of the extremity of said boom section to permit the coal to be properly delivered to a covered body form of conveyance G. This boom arrangement permits the coal to be deposited in the covered body well toward the front of the latter. The boom section (1 is made of a sufficiently greater length than the outer boom section 01 disclosed in Fig. 2 for permitting this proper loading of covered conveyances.

In Figure 4, wherein there is disclosed in detail one of the coal screening and loading booms D and a coal feeding and screening device C, the outer boom section d is illustrated as having incorporated therein a rescreening mechanism H which underlies: the upper run of the conveyor F. This rescreening device H functions to remove the degradation fines made by the coal feeding and screening mechanism 0.

The degradation fines removed by the feeding and screening mechanism C and the rescreening device H is fed inwardly along the two boom sections 01 and d by the lower run of the conveyor F. These fines are discharged off the inner ends of the boom sections d into chutes, or the like, I,

as best illustrated in Figs. 1 and 2. These chutes- I deliver the degradation fines to a screw or other form of conveyor J which carries the fines longitudinally of the local trade pocket A to be delivered to an elevator conveyor K, shown best in Figs. 1 and 2. This elevator conveyor K delivers the fines to a storage hopper L, (see Fig. 1) Where the degradation fines are accumulated awaiting proper disposal.

Figure 2 discloses suitable drive and transmission mechanism M for driving both the coal feeding and screening mechanism C and the conveyor F of a loading and screening apparatus.

Preferably, cover members N are provided for the boom sections to protect the mechanism from the weather.

It will be appreciated that a common gravity chute may be substituted for the feeding boom structures disclosed in the figures so far referred to, if desired. Such chutes will readily cooperate with the coal feeding and screening mechanism C but will not permit of careful feeding of coal to conveyances because of the force with which. a gravity chute delivers the coal to a vehicle.

The detail features of construction incorporated in the apparatus which has been selected to illustrate the invention now will be described:

Figures 4 and 5b disclose the bottom 20 of a bin at as sloping toward the discharge opening or gate 2|. The coal feeding, agitating, and screening grizzly mechanism C is properly associated with the opening or gate 2| to effectively control the rate of discharge of the coal through said opening to prevent avalanching o-r flushing of the coal through the opening and to cause the coal to be delivered in a sufliciently shallow stream to permit proper screening out of the degradation fines.

Figures 52) and '6 illustrate the details of the mechanism C. This mechanism consists of side plates 22 which are suitably joined together transversely and. are vertically swingably supported on a transverse shaft 23. In the form of the invention shown in these two figures, two transverse shafts 24 and 25 respectively are suitably journaled in the end plates 22. Each one of these shafts has properly keyed thereon. to rotate therewith a multiplicity of grizzly disks 26. The diameter of these disks is such that the disks of one shaft will overlap the disks of the adjacent shaft in the manner best illustrated in Fig. 6.

Figures 7 and 8 illustrate in detail the formation of each one of the disks 26. It will be seen that each disk is provided with any desired number of equally spaced, relatively large teeth or serrations 21. Interposed between the peripheral teeth or serrations 2i are the smaller teeth 28. Any desired number of small teeth may be interposed between adjacent large teeth or serrations 21. Each disk is provided with a hub 29 which projects in opposite directions and these hubs function to hold adjacent disks on the respective shafts 24 and 25 properly spaced from each other to permit degradation fines to be screened therebetween.

Figures 4, 5b and 6 disclose adjusting screws or rods 3!] which are properly connected to the side plates 22 and to a suitable fixed support to permit the mechanism C to be adjusted or swung vertically. This adjustment of the mechanism C permits the latter to effect different rates of feed of coal from the bin at. It will be understood that the serrations or teeth 2'! and 28 formed on the peripheries of the disk 26 will function to draw the lumps of coal from the bin a. The larger teeth or serrations 21 will function to agitate or tilt the large lumps of coal to remove from the same the fines resting thereupon to permit these fines to drop through the spaces between the grizzly disks: 23.

Figures 511 and 6 disclose a bridging plate 3! which is carried by the end plates 22 of the feeding mechanism C and functions to keep the shaft 23 free from coal dust, or the like, and to sub stantially bridge the gap between the extremity of the bottom bin wall 20- and the adjacent grizzly. These two figures also disclose a comb-like plate 32 positioned beyond the second grizzly to assist in feeding the lumps from the grizzly to a conveyor mechanism which will be described at a later point.

Figures 5a. and 5b jointly illustrate in detail the features of construction of the sectional boom D. The inner boom section d is suitably anchored to or supported on frame members of the local trade pocket structure. This inner boom section includes side walls 33 and a bottom Wall or plate 34. Extending longitudinally of the boom section 11 and suitably supported by transverse bars 35 is an upper plate 33. The plate 36 extends the full width of the boom section at to engage at its longitudinal edges the side plates 33. This upper plate 36 is interrupted from a point beneath the feeding and screening mechanism C to a point adjacent the extremity of the boom sec tion for the purpose of receiving a plurality of screening bars 31.

A conveyor supporting track 38 is positioned adjacent each side plate 33 of the boom section d and functions to support the lower run of the endless conveyor F. This conveyor is of the scraper type and includes side chains with the properly spaced, transversely extending scraper bars 39. A transversely extending, adjustable, conveyor drive shaft 40 is suitably journaled adjacent the inner end of the boom section d. This shaft 40 has properly secured thereto conveyor chain driving sprockets 4|.

By referring particularly to Figs. 4 and 6, it will be seen that the outer end of the inner boom section d is supported by angle braces 42. These angle braces have suitably journaled thereon a transverse shaft 43. Fig. 5a, discloses this shaft 43 as pivotally supporting the outer boom section at which comprises side plates 44 and a bottom plate 45. An upper plate 46 extends longitudinally of the boom section d in spaced parallelism with the bottom plate 45. This upper plate is properly supported by transversely extending brace bars 4?, in the manner illustrated. A conveyor track 48 is associated with each side plate 3d and is arranged in parallelism with the-botover the sprockets 4| and 5| of the shafts 40 and;

5!! located at the outer extremities of the two boom sections. The upper run of this conveyor is supported by the upper plates 36 and 4B of the two boom sections. The scraper bars 39 of the upper run will feed the coal along the boom sections toward the extremity of the outer section (1'. While moving the coal over the screening bars 31 and 49 of the two boom sections, the degradation fines will pass between these bars and will drop onto the bottom plates 34 and of the two boom sections. The bottom or return run of the conveyor, therefore, will move the degradation fines rearwardly of the boom to discharge the same ofi of the inner end of the boom section (1 onto the chute or trough I, (see Fig. 5b). The degradation fines screened out by the grizzly disks 25 will pass between the screening bars 31. Any degradation made by the screening and feeding mechanism C will pass between the bars of the rescreening device H. In view of these two 'flfi screening operations, lump coal will be discharged from the outer end of the boom in an extremely clean and wholesome condition.

Figures 4, 5a and 5b, disclose the cover sections N which are employed for protecting the loading boom and its associated mechanism from the weather. The inner section of the cover is suitably attached to the structure of the local trade pocket A and surrounds the opening 2| for the bin a and also encloses the coal feeding and screening grizzly structure. A hinged top panel 51 is provided for gaining access to the mechathe chain or belt 64.

nism C so that if this mechanism becomes clogged or jammed, an operator may readily free the same. The cover for the outer boom section 11' includes the arched top 58 which is suitably connected to the side wall sections 59.

Figures 4, 5b and 6, disclose the prime mover and the transmission mechanism employed for driving the conveyor F and the grizzly mechanism C. An electric motor, or the like, 60 is suitably mounted on the frame-work of the pocket A. A drive chain or belt Si is driven by the motor 6!) and is trained over a sprocket or pulley 62 which is suitably keyed to the shaft 40. This shaft, as previously described, constitutes the drive shaft for the conveyor F. The opposite end of the shaft 4! has suitably keyed thereto a sprocket or pulley 63 over which is trained a chain or belt 64 which extends to and is trained over a sprocket or pulley 65 mounted on the grizzly shaft 24. The second grizzly shaft 25 is driven from the grizzly shaft 24 by a chain or belt 66 which is trained over the sprockets or pulleys 6'! and 63 keyed to the grizzly shafts.

A chain or belt tightener mechanism, of any desired construction, is illustrated at 69 and functions to properly tighten or tension the chain or belt 6|. Suitable chain or belt'tightener mechanism 19 is employed for tightening or tensioning It will be appreciated that by varying the relative sizes of the sprockets or pulleys connected by any of the belts 6!, E4, or 65, different drive ratios may be provided between the conveyor F and the grizzly mechanism C or between the respective shafts of the said grizzly mechanism.

Figures 9 and 10 disclose a slightly modified form of coal feeding, agitating and screening grizzly. In this modification, the frame H is vertically swingably mounted upon the shaft 12 and is adjusted by means of threaded bolts or rods, (not shown), connected to flanges 74 carried by the said frame. In this modification, three grizzly shafts l5, l5 and H are journaled in the frame H. Each one of these grizzly shafts is provided with a suitable number of serrated or toothed grizzly disks 2B of the type specifically described in connection with Figs. '7 and 8.

The drive for these various grizzlies comes from a suitable electric motor, or the like, 18 and extends through the sprockets 19 and 8!! over which is trained the chain 8|. The sprocket 86 is carried by a transverse shaft 8?. which has suitably mounted on its opposite end a sprocket B3. A chain M is trained over this sprocket and a second sprocket which is suitably secured to the grizzly shaft 15. The remaining two grizzly shafts 16 and 1'! are driven from the shaft 15 by the chains 86 and 8? which are trained over sprockets 88-99 and sac-es respectively.-

This grizzly coal feeding, agitating, and screening mechanism functions in the same general manner as the mechanism C disclosed and described in connection with the preceding figures.

The various portions of the bin and loading boom with its conveyor are substantially identical and will be given the same reference characters as has been employed for these elements in the preceding figures.

Figure 11 discloses a further modified form of coal feeding, agitating and screening grizzly mechanism. In this mechanism, the adjustable frame 92 carries only a single grizzly shaft 93 which is provided with the desired series of serrated or toothed grizzly disks 26. The grizzly shaft 93 is driven by means of a sprocket 94 over which is trained a chain 95 extending from the sprocket 96 carried by the adjustable shaft 91. This latter shaft is driven by means of a sprocket 98 and a chain 99 which is suitably connected to an electric motor, or the like.

This grizzly mechanism of Fig. 11 operates substantially in the same manner as the previously described grizzly mechanisms. It cooperates with the same elements of the bin (1., the boom D and the conveyor F and for that reason these latter elements need not be specifically referred to again.

Where the termslumpsorlumpcoalare used in the specification and claims, they should not be construed as specific limitations as to the sizes of coal the apparatus is capable of handling. The apparatus is adapted for handling nut coal, egg coal, fine coal and lump coal eitherwith orwithout a considerable amount of fine lumps. If the apparatus is used on run-of-mine coal it will take out all sizes smaller than the openings in the grizzly, the feed to the grizzly, however, would have to be very small.

It will be appreciated that the coal loading and screening mechanisms embodying this invention and described above possess many desirable advantages in the handling of coal by local trade dealers.

It will be appreciated that extremely, wholesome coal will be delivered to the conveyances employed for carrying the coal to the consumers. All degradation fines will be completely removed from the coal prior to its delivery to the conveyances. The complete removal of these fines is made possible by the mannner in which the coal is fed from the bins by means of the different type of grizzly mechanisms. The screening of the coal first by the grizzly mechanisms and then by the rescreening devices carried by the outer boom sections provide ample assurance that no fines will be delivered to the conveyances along with the desired lump coal.

Delivery boom structures are provided which will enable the coal to be carefully deposited in any type conveyance without undue breakage.

The degradation fines screened from the coal during its delivery to the transportion conveyances are effectively carried away and disposed of so that they will not accumulate in an undesirable manner or at a point which would prevent efiicient operation of the local trade pocket.

It is to be understood that the forms of this invention herewith shown and described are to be taken as the preferred examples of the same and that various changes in the shape, size, and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

Having thus described the invention, I claim:

1. Apparatus of the type described comprising a bin having a perpendicular discharge opening, a rotary grizzly positioned laterally outwardly of said opening and constructed for damming the coal, feeding it through the opening at a predetermined rate, agitating the lumps to dislodge fines therefrom, screening out the fines while it is so fed, and means for bodily swinging the grizzly about an axis extending transversely of said opening to vary the rate of feed of material through said opening by changing the operative position of the grizzly relative to the opening. 2. Apparatus of the type described comprising a lump coal storage bin having a discharge opening, a rotary grizzly for damming the coal at said opening, feeding the coal through said opening and screening out the degradation fines from the lumps, a loading boom for delivering the coal from the grizzly to a conveyance, an endless scraper conveyor extending the full length of the boom and beneath the grizzly and bin with its upper run travelling toward the discharge end of the boom, upper and lower plates on the boom for supporting the runs of said grizzly, and a screening grate in the upper plate located beneath the grizzly for passing fines through to the lower plate, the lower run of said conveyor moving the fines inwardly along the lower plate to a point of discharge beneath the bin.

3. Apparatus of the type described comprising a storage bin for large lump coal having a vertical opening, a support mounted for pivotal movement outwardly of and about an axis extending transversely of said opening, a rotary shaft journaled on said support, a plurality of disks keyed to said shaft in spaced relation to screen fines therebetween, each of said disks having a plurality of peripheral serrations or teeth formed thereon with certain of the serrations or teeth, spaced around said disk, being of greater height than the remaining serrations or teeth to effect feeding and tilting of the coal lumps, and means for driving said shaft.

4. Apparatus of the type described comprising a storage bin for large lump coal having a vertical opening, a support mounted for pivotal movement outwardly of and about an axis extending transversely of said opening, a rotary shaft journaled on said support, a plurality of disks keyed to said shaft in spaced relation to screen fines therebetween, each of said disks having a plurality of peripheral serrations or teeth formed thereon with certain of the serrations or teeth, spaced around said disk, being of greater height than the remaining serrations or teeth to effect feeding and tilting of the coal lumps, means for driving said shaft, and a boom to receive the lump coal fed thereto by said disks.

5. Apparatus of the type described comprising a storage bin for large lump coal having a vertiacal opening of a size to readily pass the coal lumps, a support mounted for pivotal movement outwardly of and about an axis extending transversely of said opening, a plurality of parallel rotary shafts journaled in said support, a plurality of disks keyed to each of said shafts in spaced relation, all of said disks cooperating to screen fines therebetween, each of said disks having a plurality of teeth formed thereon with certain of the teeth being of greater height than the remaining teeth to effect feeding and tilting of the coal lumps, and means for driving both of said shafts.

6. Apparatus of the type described comprising a lump coal storage bin having a discharge opening, a boom to receive the coal from said opening, said boom including a coal supporting plate, an endless scraper conveyor for moving the coal along said plate, and a screening grate positioned in said plate beyond said bin opening to withdraw fines from the coal moving over the plate; and a rotary grizzly unit positioned outwardly of the discharge opening and above a part of the screening grate and the portion of the boom plate located between the bin opening and said grate for damming the coal at said opening, feeding the coal at a uniform rate to said boom, and tilting the lumps of coal to dislodge fines resting thereon to permit the fines to pass through the screening grate.

'7. Apparatus of the type described comprising a lump coal storage bin having a discharge opening, a boom to receive the coal from said opening, said boom including a coal supporting plate, an endless scraper conveyor for moving the coal along said plate, and a screening grate positioned in said plate beyond said bin opening to withdraw fines from the coal moving over the plate; and a rotary grizzly unit positioned outwardly of the discharge opening and above at least a part of said screening grate and the portion of the boom plate located between the bin opening and said grate for damming the coal at said opening, feeding the coal at a uniform rate to said boom, and tilting the lumps of coal to dislodge fines resting thereon to permit the fines to pass through the screening grate, said grizzly including a plurality of parallel driven shafts and a plurality of toothed coal feeding and tilting disks mounted on said shafts, certain of said disk teeth being larger than the remainder to effect said coal lump tilting operation.

8. Apparatus of the type described comprising a lump coal storage bin having a discharge opening, a boom to receive the coal from said opening, said boom including a coal supporting plate, an endless scraper conveyor for moving the coal along said plate, and a screening grate positioned in said plate to withdraw fines from the coal moving over the plate; and a rotary grizzly unit positioned outwardly of the discharge opening and above the boom for damming the coal at said opening, feeding the coal at a uniform rate to said boom, and tilting the lumps of coal to dislodge fines resting thereon to permit the fines to pass through the screening grate, means for supporting the grizzly unit for pivotal movement relative to the bin opening to vary the feeding rate of the coal by changing the operative position of the grizzly unit relative to said opening, and means for pivoting the grizzly unit.

9. Apparatus of the type described comprising large lump coal delivering means, a rotary grizzly unit positioned to receive coal from said delivery means and being constructed and arranged to feed the coal at a uniform rate, tilt the large coal lumps to dislodge fines resting thereon and screen fines therethrough, a boom extending beneath and beyond said grizzly unit to receive the lump coal and fines from said unit, said boom including coal supporting plates arranged one above the other, a screening grate positioned in the upper plate and extending partly beneath the grizzly unit and partly beyond the discharge side of said unit to pass to the lower plate the fines screened by said unit, and an endless scraper conveyor having its runs operatively associated with the boom plates for moving the coal lumps in one direction along the upper plate and for moving the fines in the opposite direction along the lower plate.

10. Apparatus of the type described comprising storage bin for large lump coal having a discharge opening, the diameter of which will permit unobstructed passage of large coal lumps, a grizzly unit positioned entirely laterally of the top margin of said opening and forming an obstruction which will dam the coal at said opening, said grizzly unit comprising a plurality of rotary disks properly spaced to permit fines to pass therebetween, the periphery of each disk being of such,

irregular contour as to cause positive feeding of the dammed large coal lumps and tilting of the same to dislodge fines resting thereon, a boom extending beneath and beyond said grizzly unit to receive the lump coal and fines from said unit, said boom including coal supporting plates arranged one above the other, screening means interrupting the upper plate and extending partly beneath the grizzly unit and partly beyond the discharge side of said unit to pass to the lower plate the fines screened by said unit, and an endless scraper conveyor having its runs operatively associated with the boom plates for moving the large coal lumps in one direction along the upper plate and for moving the fines in the opposite direction along the lower plate.

11. Apparatus of the type described comprising a storage bin for large lump coal having a discharge opening, the diameter of which will permit unobstructed passage of large coal lumps, a grizzly unit positioned entirely laterally of the top margin of said opening and forming an obstruction which will dam the coal at said opening, said grizzly unit being'constructed and arranged to feed the coal at a uniform rate, tilt the large coal lumps to dislodge fines resting thereon and screen fines therethrough, a boom extending beneath and beyond said grizzly unit to receive the lump coal and fines from said unit, said boom including coal supporting plates arranged one above the other, a screening grate positioned in the upper plate and extending partly beneath the grizzly unit and partly beyond the discharge side of said unit to pass to the lower plate the fines screened by said unit, and an endless scraper conveyor having its runs operatively associated with the boom plates for moving the coal lumps in one direction along the upper plate and for moving the fines in the opposite direction along the lower plate.

12. Apparatus of the type described comprising a storage bin for large lump coal having a discharge opening, the diameter of which will permit unobstructed passage of large coal lumps, and a grizzly unit positioned entirely laterally of the top margin of said opening and forming an obstruction which will dam the coal at said opening, said grizzly unit comprising a support mounted for pivotal movement about an axis extending transversely of said opening, a rotary shaft journalled on said support, a plurality of disks keyed to said shaft in spaced relation to screen fines therebetween, each of said disks having a plurality of peripheral serrations formed thereon with certain of the serrations, spaced around the disk, being of greater height than the remaining serrations to effect feeding and tilting of the coal lumps, and means for driving said shaft. 13. Apparatus of the type described comprising a storage bin for large lump coal having a discharge opening, the diameter of which will permit unobstructed passage of large coal lumps, and a grizzly unit positioned entirely laterally of the top margin of said opening and forming an obstruction which will dam the coal at saidopening, said grizzly unit comprising a support mounted for pivotal movement about an axis extending transversely of said opening, a plurality of parallel rotary shafts journalled in said support, a plurality of disks keyed to each of said shafts in spaced relation, all of said disks cooperating to screen fines therebetween, each of said disks having a plurality of teeth formed thereon with certain of the teeth being of greater height than the remaining teeth to effect feeding and tilting of the coal lumps, and means for driving both of said shafts.

14. Apparatus of the type described comprising a storage bin for large lump coal having a discharge opening, the diameter of which will permit unobstructed passage of large coal lumps, a rotary grizzly unit positioned entirely laterally of the top margin of said opening and forming an obstruction which will dam the coal at said opening, said grizzly unit comprising a plurality of rotary disks properly spaced to permit fines to pass therebetween, the periphery of each disk being of such irregular contour as to cause positive feeding of the dammed large coal lumps and tilting of the same to dislodge fines resting thereon, a sectional boom extending beneath and beyond said grizzly unit to receive the lump coal and fines from said unit, said sectional boom including coal supporting plates arranged one above the other, screening means interrupting the upper plate and arranged partly beneath the grizzly unit and partly beyond the discharge side of said unit to pass to the lower plate the fines screened by said unit and dislodged from the lumps after the latter have been deposited on the upper plate, an endless scraper conveyor having its runs operatively associated with the boom plates for moving the coal lumps to the discharge end of the boom along the upper plate and for moving the fines in the opposite direction along the lower plate, and means for vertically adjusting the discharge end of the outer boom section so that the lumps discharged from the same may be deposited in a conveyance, or the like, without danger of breakage.

15. Apparatus of the type described comprising a storage bin for large lump coal having a discharge opening, the diameter of which will permit unobstructed passage of large coal lumps by gravitational flow, a grizzly unit positioned entirely laterally of the top margin of and immediately adjacent the bottom margin of said opening and being arranged to form an operating zone inclined in the opposite direction to the direction of gravitational flow of said coal to thereby dam the coal at said opening against said gravitational flow, said grizzly unit comprising a pluralty of parallel sets of rotary discs properly spaced to permit fines to pass therebetween, the periphery of each disc being of such irregular contour as to cause positive feeding of the large coal lumps from their dammed position at said opening and to tilt the same to dislodge fines resting thereon, and means for bodily adjusting the grizzly unit about an axis extending transversely of said opening to vary the inclination of said operating zone.

16. Apparatus of the type described comprising a storage bin having a discharge opening, a support mounted for movement in a path extending vertically of said opening, a rotary shaft journaled on said support, a plurality of discs keyed to said shaft in spaced relation to screen fines therebetween, each of said discs having a plurality of peripheral serrations or teeth formed thereon with certain of the serrations or teeth, spaced around said disc, being of greater height than the remaining serrations o-r teeth, said last mentioned teeth being so arranged as to give the disc a substantially triangular contour in side elevation which will effect feeding and tilting of the coal lumps, and means for driving said shaft, the movement of the support transversely of said opening effecting a variation of therate of feed effected by said discs.

17. Apparatus of the type described comprising a storage bin having a discharge opening a support mounted for movement in a path arranged vertically of said opening, a plurality of parallel rotary shafts journaled in said support, a plurality of discs keyed to each of said shafts in spaced relation to the screen fines therebetween, each of said discs having a plurality of peripheral serrations or teeth formed thereon with certain of the serrations or teeth, spaced around said disc, being of greater height than the remaining serrations or teeth, said last mentioned teeth being so arranged as to give the disc a substantially triangular contour in side elevation which Will eifect feeding and tilting of the coal lumps, and means for driving said shaft, the movement of the support transversely of said opening effecting a variation of the feeding rate of said discs.

18. Apparatus of the type described comprising a supply of lump coal, a conveyor unit to receive the coal from said supply, said conveyor unit including a coal supporting plate, means for moving the coal along said plate, and a screening grate positioned beyond the point of delivery of coal from the supply to the conveyor unit to withdraw fines from the coal moving over the plate; and a rotary grizzly unit positioned between the supply and the screening grate to receive the coal delivered from the supply, to tilt the coal lumps to dislodge fines resting thereon to permit the fines to be passed through the screening grate, and to feed the lumps. to the conveyor unit.

19. Apparatus of the type described comprising a storage bin for large lumps of coal having a vertical opening of a size to readily pass the largest coal lumps, a rotary grizzly, including a plurality of vertically arranged spaced discs, extending substantially the width of and positioned outwardly of and adjacent the lower edge of said opening so as to dam the'coal at the opening, feed the coal through the opening and screen out the fines from the lumps, and means for bodily adjusting the grizzly through a path extending vertically of the opening to vary the damming action and rate of feed through said opening by changing the operative position or" the grizzly relative to the opening.

GEORGE S. JAXON. 

